regcompare: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/lib64/libreoffice/sdk/bin/regcompare - from package: libreoffice-sdk

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/lib/libreoffice/sdk/bin/regcompare - from package: libreoffice-dev

You may install the required package with command apt-get install {package}

Error in other languages:
regcompare: bevel nie gevind nie
regcompare: comandă negăsită
regcompare: comando não encontrado
regcompare: commande introuvable
regcompare: command not found
regcompare: käsku ei ole
regcompare: không tìm thấy lệnh
regcompare: komanda nerasta
regcompare: Kommando nicht gefunden.
regcompare: kommandot finns inte
regcompare: komut yok
regcompare: nie znaleziono polecenia
regcompare: níor aimsíodh an t-ordú
regcompare: no se encontró la orden
regcompare: no s'ha trobat l'ordre
regcompare: opdracht niet gevonden
regcompare: parancs nem található
regcompare: perintah tidak ditemukan
regcompare: príkaz nenájdený
regcompare: příkaz nenalezen
regcompare: команда не найдена
regcompare: командата не е открита
regcompare: 命令找不到
regcompare: コマンドが見つかりません